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    <meta charset="UTF-8">
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    <title>Document</title>
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<body>
     <script>
      let nm=function(name){
        return name
      }
      let H=nm(name)   
        let hi = function(name) { 
            console.log( name)
            return name
        }
        hi("zx")
        let aa = name =>
           {name = "hi!" + name
        alert("你好！！！" + name)}

        aa("zs")
        let a = 20 
        console.log(typeof a) 

        let vv = "你好！！！" 
        console.log(typeof vv) 

        let n = "null" 
        console.log(typeof n) 

        let k = {
                name: "zhangsan",
                age: 20
            } 
        console.log(typeof k) 

        let w = undefined
        console.log(typeof w) 

        console.log(typeof nm) 

        let arr = [1, 2, 3, 7, 9]
        console.log(typeof arr) 
        console.log(arr instanceof Array) 
        console.log(Array)
        console.log(nm)

        let arr1 = new Array("aaa", "bbb", "xxx") 
        console.log(arr1 instanceof Array)
    </script>
</body>
</html>